IEC 60404-8-4:2013

Overview

IEC 60404-8-4:2013 is an international standard published by the International Electrotechnical Commission (IEC) that specifies the requirements for cold-rolled non-oriented electrical steel strip and sheet delivered fully processed and fully annealed. This standard focuses on materials used in magnetic circuits, defining the grades based on nominal thicknesses of 0.35 mm, 0.50 mm, 0.65 mm, and 1.00 mm. It addresses the essential magnetic, geometric, and technological properties along with inspection and testing protocols to ensure quality and consistency.

Key Topics

• Material Scope: Cold-rolled non-oriented electrical steel strip and sheet, supplied in fully processed and annealed condition, intended for magnetic circuit construction. The standard excludes semi-processed materials.
• Grades and Thicknesses: Specifies steel grades including new introductions such as M210-35A 5 and M230-50A 5, covering thicknesses mainly 0.35 mm, 0.50 mm, 0.65 mm, and 1.00 mm.
• Magnetic Properties: Defines precise magnetic polarization, specific total loss, anisotropy of loss, and other parameters measured primarily using the Epstein method.
• Geometric Characteristics: Includes tolerances on thickness, width, length, edge camber, flatness (wave factor), and residual curvature.
• Technological Characteristics: Covers density, stacking factor, number of bends, and internal stress.
• Inspection and Testing: Outlines sample selection, specimen preparation, test methods for magnetic and geometrical properties, and retesting procedures.
• Delivery and Marking: Specifies production processes, form of supply, surface conditions, suitability for cutting, marking, labeling, packaging, and complaint procedures.

Practical Applications

IEC 60404-8-4:2013 is vital for manufacturers, suppliers, and end-users in industries where magnetic materials are critical components, such as:

• Electric Motors: Optimal magnetic properties improve efficiency and reduce energy loss in motors.
• Transformers: Ensures reliability and performance through strict control of electrical steel quality.
• Magnetic Circuits: Materials meeting this standard provide uniform magnetic characteristics essential for precision-engineered magnetic circuits.
• Electrical Equipment Manufacturing: Assists in quality control and material selection for products demanding high-performance magnetic materials.
• Research and Development: Assists in the development of new steel grades with improved magnetic properties suitable for evolving technological needs.

Using steel strip and sheet conforming to IEC 60404-8-4 ensures compliance with globally recognized quality benchmarks, facilitating international trade and reducing variability in magnetic properties critical for electrical device performance.

Related Standards

• IEC 60404 Series: Comprehensive set of standards covering magnetic materials, including methods of measurement and specifications for different steel classes.
• IEC 60404-2: Specifies measurement methods for magnetic properties using the Epstein frame.
• IEC 60404-9: Details methods for determining geometric characteristics of magnetic steel sheets and strips.
• IEC 60404-13: Covers measurements of density, resistivity, and stacking factor essential to electrical steel characterization.
• ISO 404: General technical delivery requirements for steel and steel products, supporting consistent supply chain quality.
• ISO 7799: Testing metallic materials for bending properties, relevant to assessing technological characteristics of steel strips.
• ISO 10474: Guidelines on inspection documents, assisting in traceability and compliance documentation.

Keywords: IEC 60404-8-4, cold-rolled non-oriented electrical steel, magnetic materials, electrical steel strip, fully processed steel, magnetic properties, electrical steel sheet, Epstein method, steel grades, geometric tolerances, magnetic circuits, electrical steel standards, IEC magnetic steel standards.